akhiok - water and sewer critical repairsomb.alaska.gov/ombfiles/14_budget/capbackup/proj60109.pdf1)...

Total Project Snapshot Report2013 Legislature TPS Report 60109v1

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Agency: Commerce, Community and Economic DevelopmentGrants to Municipalities (AS 37.05.315)

Federal Tax ID: 92-0045466Grant Recipient: Akhiok

Project Title: Project Type: Maintenance and Repairs

Akhiok - Water and Sewer Critical Repairs

State Funding Requested: $955,000 House District: 35 / ROne-Time Need

Brief Project Description:This project will provide a modular water treatment plant, a water storage tank, and repair the sewageocean outfall.

Funding Plan: Total Project Cost: $1,130,000 Funding Already Secured: ($175,000)FY2014 State Funding Request: ($955,000)Project Deficit: $0 Funding Details:

In 2012, The Alaska Native Tribal Health Consortium provided $175,000 of funding for project design and limited immediate repairs

Detailed Project Description and Justification:Akhiok's water and sewer system has critical deficiencies that threaten public health and the environment. The watertreatment system is not in compliance with EPA regulatory drinking water requirements (insufficient water filtration andinadequate disinfection time) therefore the entire community is on a boil water notice. The community does not have theequipment or facilities required to properly maintain the sewage collection system, and, consequently, components of thesystem are in poor condition and/or have failed e.g. the community's sewage outfall line is severed and currently dischargessewage to a beach in the middle of town that children routinely swim in.

The ANTHC and the City of Akhiok have pursued funding from traditional sources, but due to the small size of thecommunity and the diverse nature of the proposed scope, traditional funding sources seem unlikely.

The ANTHC has contributed $175K for this project to1) document and provide solutions construction costs for Akhiok's most critical water and sewer deficiencies2) design a small containerized water treatment plant, and3) complete immediate repairs to the water treatment plant and distribution system to prevent the complete loss of the entiresystem.

This legislative grant request will1) construct the small containerized water treatment plant and connect it to the system providing adequate treatment,2) Provide a disinfection tank to ensure adequate time,3) repair the sewage outfall line to remove the sewage from the beach, and4) provide equipment to pump the community septic tanks and a septic tank sludge disposal area to ensure the outfall line

For use by Co-chair Staff Only:

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Contact Name: Astrid RoseContact Number: 465-3271

2:00 PM 5/9/2013

Total Project Snapshot Report2013 Legislature TPS Report 60109v1

does not separate again.

Project Timeline:August 2013 - Project AwardedSeptember to December 2013 - Construct containerized water plant in AnchorageApril 2014 - Mobilize to Akhiok and begin onsite constructionApril 2014 to June 2014 - Complete all onsite constructionJuly 2014 - Demobilize

Entity Responsible for the Ongoing Operation and Maintenance of this Project:The residents of Akhiok through the collection of water and sewer user fees

Grant Recipient Contact Information:Name: Linda AmodoTitle: MayorAddress: P.O. Box 5050

Akhiok, Alaska 99615Phone Number: (907)836-2229Email: [email protected]

Has this project been through a public review process at the local level and is it a community priority? X Yes No

For use by Co-chair Staff Only:

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Contact Name: Astrid RoseContact Number: 465-3271

2:00 PM 5/9/2013

MEMORANDUM STATE OF ALASKA DEPARTMENT OF ENVIRONMENTAL CONSERVATION Department of Water, Operations Assistance Program Remote Maintenance Worker 555 Cordova St, 4th fl. Anchorage, AK 99501 Office 269-7609 Fax 269-7509 DATE: 1/25/13 TO: City of Akhiok FROM: Steven W. Evavold, ADEC, and Remote Maintenance SUBJECT: Akhiok improvements Good Day, I’ve had the pleasure of working with the good people of Akhiok Alaska for the last 14 years. The critical needs of your community have been many from the start and are well documented. Public health is threatened by not having the capability in the water plant of producing potable water with the quality required by EPA standards. It cannot meet the Surface water treatment rule nor does the system have the ability to provide any contact time for chlorine to react and disinfect. Chlorine is injected and water is sent directly out to the distribution loop. There is inadequate water storage with just two 10,000 gallon tanks. These tanks “float” on the system; meaning the water that does not go to demand is pumped up to overflow. A break in the water mains will drain the 20,000 gallons in the tanks, the water mains, and residences in a very short time. The water mains are old ductile iron and very brittle PVC and need replacing. There is currently no means to pump the septic tanks and discharge to a lagoon. The ocean outfall was documented in 1981 as “Rising and falling with the tide”. The community had no choice but to cut the outfall at the beach to relieve the back up of septage. Much of the outfall still is seen floating and is a threat to the maritime traffic. Not having potable water for the new clinic and the 22 students in the school is dangerous and has to stop. There is no more room for band aides here. Thanks for your consideration. State of Alaska, ADEC Remote Maintenance Worker Steven W. Evavold

Akhiok Water and Sewer System Feasibility Study Update

Prepared By: Michael Soltis, P.E.

December 2012

Akhiok, Alaska Water and Sewer System Feasibility Study Update

Contents Introduction ..................................................................................................................... - 1 - Background ..................................................................................................................... - 1 -

Site Description ........................................................................................................... - 1 - Community Description .............................................................................................. - 1 - Water System Description .......................................................................................... - 2 - Existing Sewage Collection System ........................................................................... - 2 - Previous Studies .......................................................................................................... - 2 -

Water and Sewer System Deficiencies ........................................................................... - 2 - Critical Water System Deficiencies ............................................................................ - 3 - Major Water System Deficiencies .............................................................................. - 7 - Critical Sewage System Deficiencies ......................................................................... - 7 - Major Sewage System Deficiencies.......................................................................... - 10 -

Water and Sewer System Corrective Action Alternatives ............................................ - 11 - Alternative 1 (worst case scenario) ........................................................................... - 11 - Alternative 2 (best case scenario) ............................................................................. - 11 - Alternative 3 (minimum corrective action scenario) ................................................ - 12 -

Discussion of Corrective Action Alternatives .............................................................. - 12 - Alternative 1.............................................................................................................. - 12 - Alternative 2.............................................................................................................. - 12 - Alternative 3.............................................................................................................. - 12 -

Conclusions/Recommendations .................................................................................... - 13 -

Figures 2008 Department of Economic Development (DCED) Akhiok Area Map 2008 DCED Akhiok Community Map


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Introduction

Akhiok’s water and sewer system has critical deficiencies that threaten public health and the environment. Many of these deficiencies were documented in a 2003 Sanitation Feasibility Study prepared by GV Jones and Associates. However, due to Akhiok’s relatively low population, a competitive funding environment, and relatively high project costs, none of the needed improvements identified by the 2003 study were funded or completed. The Alaska Native Tribal Health Consortium (ANTHC), Division of Environmental Health and Engineering (DEHE) has conducted this study to identify potential low-cost alternatives for addressing Akhiok’s water and sewer system deficiencies. The improvements identified in this study include repairs/upgrades to the existing systems and the construction of new infrastructure.

Background

Site Description

Akhiok is located at the southern end of Kodiak Island at Alitak Bay. It lies 80 miles southwest of the City of Kodiak and 340 miles southwest of Anchorage. The community lies at approximately 56.945560° North Latitude and -154.170280° West Longitude. (Sec. 28, T037S, R031W, Seward Meridian.) Akhiok is located in the Kodiak Recording District. The area encompasses 7.9 sq. miles of land and 2.5 sq. miles of water.

The climate of the Kodiak Islands is dominated by a strong marine influence. There is little or no freezing weather, moderate precipitation, and frequent cloud cover and fog. Severe storms are common from December through February. Annual precipitation is 35 inches. Temperatures remain within a narrow range, from 25 to 54 °F.

Community Description

Akhiok’s population is 82 (2011 DCCED certified estimate). According to Census 2010, there were 27 housing units in the community and 19 were occupied. Public sector employment and seasonal work provide cash flow in the community. Almost all of Akhiok's residents depend heavily on subsistence fishing and hunting. Salmon, crab, shrimp, clams, ducks, seal, deer, rabbit, and bear are utilized. There is one school located in the community, which is attended by 17 students. Local hospitals or health clinics include the Akhiok Health Clinic, which is a Primary Health Care Facility. Electricity is provided by the City of Akhiok. The city generators are typically shut down at night during the summer to save fuel and lower operational costs.


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Water System Description

Akhiok’s obtains raw water from a surface water impoundment. The raw-water gravity flows to the water treatment plant, where it is filtered through two 48-inch diameter sand filters and then chlorinated. A pressure booster pump is required to pressurize the distribution system, which uses two 10,000-gallon WSTs (located about 55 feet up-gradient of the raw water source) to provide water storage and maintain water distribution system pressure.

Existing Sewage Collection System

Akhiok has a gravity sewage collection system with three zones. Sewage gravity flows from homes located in each zone into a septic tank serving that zone. The sewage from all three septic tanks is then combined into a single ocean outfall line that discharges in Akhiok Bay.

Previous Studies

A Sanitation Feasibility Study for Akhiok was completed in February 2003 by GV Jones and Associates. This study presented a detailed description of Akhiok’s water, sewer, and solid waste facilities, and provided recommendations for needed improvements and additions to the existing infrastructure.

Key recommendations/findings from the 2003 feasibility study are listed below:

• Increase raw water storage capacity (from 550,000 gallons to 850,000 gallons)

• Construct a new water treatment plant using a direct filtration treatment process

• Construct a new water storage tank (318,000 gallons) and new tank fill and draw lines.

• Replace portions of the existing water distribution system with six-inch mains

• Replace the water services for all homes with arctic services

• Provide a two-cell facultative lagoon, sewage lift station, and approximately one-mile sewage force main for disposing sewage. Abandon the ocean outfall.

• Provide a new solid waste landfill

Total costs in June 2002 dollars to complete the above work were estimated at about $5.6 million. Due to lack of funding, none of the above improvements were completed.

Water and Sewer System Deficiencies

Akhiok’s water and sewer system has many deficiencies. For clarity in this report, these deficiencies are referred to as critical deficiencies, major deficiencies, or minor deficiencies. A critical deficiency is a deficiency that poses an imminent threat to the


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public health and/or the environment, typically associated with complete failure of a portion of the system. Major deficiencies are significant deficiencies that should be addressed to improve the overall operability, sustainability, and/or performance of the system and to prevent imminent critical deficiencies. Minor deficiencies, which would include deficiencies such as water distribution system leaks, freezing water/sewer services, etc., are not addressed in this report.

Opinion-of-capital-cost estimates for the proposed improvements have been prepared based on ANTHC’s 2009 Sanitation Deficiency System (SDS) cost estimator tool, supplemented with information from more recent construction projects. These estimates are provided for general guidance in project evaluation and funding and for comparative purposes.

Critical Water System Deficiencies

The following deficiencies include both water treatment process deficiencies and water-system infrastructure deficiencies. Note that the listed water treatment process deficiencies are considered “critical,” because they represent violations of primary water treatment regulations that have been established by the EPA to protect public health by preventing waterborne illnesses.

1. Akhiok’s water treatment system does not meet the requirements of the EPA’s 1989 SWTR.

The 1989 SWTR requires 3-log inactivation/removal for Giardia and 4-log inactivation/removal for viruses. The required inactivation/removal is typically achieved through a combination of filtration and chlorine disinfection. Akhiok’s existing sand filtration system does not use a coagulant and is only eligible for a 1-log removal credit. The remaining inactivation therefore must occur through chlorine disinfection, which requires chlorine reaction time. This reaction time is typically provided by the WST(s) in a water distribution system, where all water must pass through the WST(s) before it is sent to the consumer. Akhiok’s WSTs currently have a common fill/draw line; water flows to/from the tanks through the same line. Given this configuration, chlorinated water can bypass the WSTs and go directly to the public without receiving the required chlorine contact time. Note that even if Akhiok’s existing WSTs were piped differently, they are not large enough to provide the required contact time without the use of special baffling and/or other measures.

There are several potential options for providing the required chlorine contact time; provide a new WST with a dedicated fill line, perform modifications to use the existing WSTs, or install a pressurized, baffled, chlorine contact time vessel.

A new WST that is adequately sized to provide the required chlorine contact time could be constructed. The 2003 Sanitation Feasibility Study identified several appropriate locations for a new WST. Regardless of the location, a new WST fill line would be required so all of the water treated at the WTP would pass through


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the new WST and receive adequate chlorine contact time before entering the distribution system. Estimated costs for a new WST and fill line are $580K

Akhiok’s existing WSTs could be used for chlorine contact time (CT) tanks if a new fill line is installed for the tanks and the existing fill/draw line is repurposed as a dedicated draw line. The WSTs would likely need to be plumbed in parallel, baffled, and/or have a large diameter fill pipe to provide the required contact time before the water enters the distribution system. Estimated costs for providing a new fill line and required modifications for providing the required contact time are $400K.

A pressurized, baffled, chlorine contact-time vessel could be installed downstream of the WTP to provide the required disinfection before the water entered the distribution system. This option would not require a new fill line for the existing WTP. This option would also allow the water distribution system to remain pressurized if the raw water booster pump was inactive for an extended period of time. Estimated costs for providing a new baffled chlorine contact tank are $120K.

One of Akhiok’s 10,000 Gallon WSTs (the other WST is directly behind this one)


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2. Akhiok’s WTP building has reached the end of its design service life and poses a life-safety threat to the operator and/or any other occupant.

The Akhiok WTP building is in very poor condition, with missing roofing panels, rotting structural members, and differential foundation settlement. The electric service panel has experienced a hot arcing fire that has disabled some of the building’s electrical circuits. One of the two sand pressure filters is inoperable due to a failed solo-valve. The costs to refurbish the existing facility are considered comparable to replacing the existing facility in kind.

Akhiok’s WTP should be replaced with a new facility. Ideally, a new building would be constructed similar to one of the recently constructed facilities in Ouzinkie, Larsen Bay, Old Harbor, and Port Lions. Construction costs for these facilities have averaged about $3M, including treatment equipment.

It is possible to install the required equipment in a portable structure, such as a shipping container, for a fraction of the price of a completely new facility. This type of system should be considered temporary, but could provide the required treatment for a period of years until funding for a more permanent facility is secured. A similar temporary system was used for a couple of years in Tyonek until a new WTP was constructed. Estimated costs for obtaining and modifying shipping containers for containing water treatment equipment are $100K.

Akhiok’s existing WTP


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3. Akhiok’s water treatment system does not meet the requirements of the EPA’s 2002 Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR).

The LT1ESWTR requires treatment systems to provide 2-1og removal for cryptosporidium. Akhiok’s current treatment system is only eligible for a 1-log removal credit. A 2-log removal credit could be achieved using a modern treatment process. Appropriate modern treatment processes include bag filtration, membrane filtration, or sand filtration with a coagulant.

Based on raw water samples collected in August 2012, bag filters are not considered a feasible solution because the water periodically contains too much organic material for bag filters to be used efficiently. The expected change-out frequency for bag filters is expected to drive monthly bag replacement costs of greater than several thousand dollars, which is not a sustainable expense for a community the size of Akhiok.

Membrane filtration is another possible solution. An appropriate membrane system would clean itself at little or no expense during normal operation, and the membranes could last for five years or more before requiring replacement. From a operational-cost perspective, membranes are therefore a viable solution. However, a key limitation to a membrane system is its capacity. A 5 gpm membrane system can only treat 5 gpm. Based on Akhiok’s population and typical water usage, a 5 gpm system should provide adequate capacity. However, most of Akhiok’s filtered water is currently lost to leaks in the distribution system and a 25 to 30 gpm treatment system would be required to meet current water demands. A 30 gpm membrane system would cost about $420K (equipment only), and may not be economically feasible from a capital cost perspective. If most of the leaks are fixed, a smaller system could be installed (10 gpm ~ $230K – equipment only). However, the existing water distribution system is old and new leaks are not considered just a possibility, they are considered a certainty. The consequence is that there may be times when a membrane system may not be able to satisfy demands until the leaks are fixed, which could take from days to years depending on available resources. Therefore, a more conservatively sized membrane system (30 gpm) would be recommended, with equipment costs beginning at about $420K. (note that this price would include installation of the equipment)

A sand filtration system with a coagulant is considered the most reliable and versatile treatment systems that would provide the required treatment. This type of system can be used over a wide range of flow rates and is effective for treating raw water with wide variations in quality. A sand filtration system with a coagulant can operate completely under gravity flow, provided sufficient driving head is available. Successful use of a coagulant requires the use of modern water treatment equipment incorporating key features including a streaming current detector, air scour blower, custom filter underdrain, and some automation. Equipment costs for a sand filtration system with coagulant that could treat up to about 50 gpm are about $125k. Labor associated with installation and preparation is estimated at about an additional $125K, for a total of about $250K.


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Major Water System Deficiencies

1. Akhiok’s raw water source periodically lacks adequate capacity, resulting in water shortages.

Akhiok’s existing water source consists of a mountain reservoir filled by runoff from snowmelt and rain. This reservoir periodically does not have adequate recharge to satisfy community demands. There has been a need to fly in drinking water in the past. Previous evaluations have determined that the best way to increase the reliability of this source would be to increase its storage capacity by raising the reservoir dikes and providing an impermeable liner to reduce seepage losses.

Estimated costs for improving the existing raw water source are about $600K.

Akhiok’s raw water reservoir

Critical Sewage System Deficiencies

1. Akhiok’s community outfall line is severed at the beach, exposing residents to sewage.


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Akhiok’s outfall line has had problems with plugging in the past. Some of these problems are associated with failed anchor weights on the outfall line that allowed portions of the outfall to “float” slightly, creating low points in which solids could accumulate. The accumulated solids then likely began undergoing anaerobic decomposition, which released gasses into the submerged pipe. These gasses accumulated at the high points of the submerged pipe, and caused portions of the pipe to float to the surface of Akhiok Bay. Residents in Akhiok have reported shooting at the pipe, which release the gasses and allowed the pipe to sink back down.

Over time, solids accumulation in the outfall line reached the point where it could not be cleared with local equipment. The community abandoned the failed outfall line by cutting it off near the beach.

Potential alternatives to address the problem of raw sewage being discharged to the beach include the construction of a sewage lagoon for managing wastewater, construction of a new community outfall line, or repairing the existing outfall line.

A new sewage lagoon would require an appropriate site, a sewage lift station, and a force main between the lift stations and the lagoon. One advantage of this approach is that the three community septic tanks could be abandoned. However, a wastewater lagoon may not be permissible in Akhiok from a regulatory perspective. Based on recent discussions with ADEC regulators, a wastewater lagoon in Akhiok is considered likely to fail, and it may not be possible to obtain approval to construct or operate such a facility. This option is not recommended.

A new outfall line would be effective for directing wastewater an appropriate distance from the community. The outfall line could operate under gravity or be pressurized. A pressurized outfall line would be smaller and less expensive to construct than a gravity outfall line, and would be less susceptible to clogging from accumulated solids. However, a pressurized outfall line would require a lift station and new gravity sewer piping to combine the outfalls near the shoreline. Although the lift station would be relatively simple and reliable, it would add new electrical (pumping) and O&M costs to the water and sewer system that are not incurred now. Total capital costs for this alternative are about $650k.

A new gravity outfall is the preferred potential solution in term of O&M costs. However, a new gravity outfall line would be susceptible to the same problems as the existing failed gravity outfall line. The existing gravity outfall line likely failed due to a combination of poor anchorage and solids accumulation. Current outfall anchoring methods are unlikely to fail within a 50-year period. Solids accumulation should not be an issue if the septic tanks are maintained and mechanisms are installed to allow routine maintenance flushing of the outfall line. Estimated costs for a new gravity sewage outfall line are $520K.

Repairing the existing outfall line is the lowest cost potential solution. Similar repairs have been conducted on other failed outfall lines. A barge and lifting equipment would be required. The end of the existing outfall line would be located and lifted to the surface. The barge would then follow the path of the


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existing outfall line, lifting the outfall on one side and setting it down on the other side, while replacing the anchors and patching holes. Estimated costs for repairing the existing outfall line are about $300K.

Akhiok at high tide. The existing outfall is cut near the beach and is floating to the surface in the above photograph.

2. Akhiok does not have a pumper vehicle for maintaining the community septic tanks

This is considered a critical deficiency because lack of septic tank maintenance will lead directly to failure of a sewage outfall (current situation in Akhiok).

Alternatives to address this deficiency include purchasing a new pumper vehicle ($125k) or a new trailer-mounted pump and tank ($60k). A used vehicle is not recommended unless it can be hand-selected by a qualified mechanic familiar with this type of equipment.

3. Akhiok does not have a sludge storage or disposal facility.

This is considered a critical deficiency for similar reasons. There is little benefit to providing a means to pump out the septic tanks if there is not a suitable place to

Akhiok’s sewage outfall discharges here


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dispose the solids. Akhiok currently pumps their septic tanks directly onto the beach at high tide using a trash pump.

Alternatives for disposing the septage sludge include dewatering and land-filling, or disposal in a sludge storage facility. Dewatering can be accomplished using specialized mechanical dewatering equipment or a simple trench. The mechanical dewatering system includes the addition of a coagulant and filtering of solids. The equipment is somewhat labor intensive to use and must be properly maintained. The operator will be in close contact with the sludge and will require stringent use of appropriate protective gear to prevent exposure. Dewatering equipment is not considered an attractive alternative in Akhiok because it is technically challenging to operate and would be expensive for the community to maintain.

The simple trench alternative would consist of

1. Opening a trench in a permitted area,

2. Pumping the septic sludge into the trench

3. Allowing the sludge to dewater

4. Applying lime to the remaining solids

5. Covering the trench with fill material

The simple trench alternative would require an appropriate site. The areas down-gradient of the site would need to be surveyed for potential seeps and/or surface water bodies that could be impacted. Groundwater monitoring wells may be required to verify that nitrate contamination does not exceed regulatory limits at the downgradient property boundaries. Costs for evaluating use of the simple trench method would include engineering and permitting costs, about $25K. Costs to develop an appropriate site are unknown at this time. Other costs would be related to use of the backhoe owned by the city and lime costs, and would be considered O&M type expenses.

A sludge disposal facility would consist of a lined holding cell and a percolation cell. This type of facility is proposed for use in nearby Ouzinkie and Port Lions. The holding cell would be sized to hold about 15 to 20 years of septic solids. Most of the hydraulic loading to the cell would consist of precipitation, which would overflow into the percolation cell. These facilities rarely give off an odor except for when sludge is being pumped into them. These type of facilities are also very low maintenance and do not require lime to neutralize the waste each time it is disposed. Estimated costs for a sludge disposal facility are about $700K.

Major Sewage System Deficiencies

1. The community’s three existing steel septic tanks are nearing the end of their useful service life



These steel septic tanks are installed in a corrosive marine environment and are likely either currently leaking or soon to be leaking into groundwater that daylights at the beach, which poses a health hazard. Estimated costs for replacing all three septic tanks are $450K.

Water and Sewer System Corrective Action Alternatives

Several alternatives were evaluated for correcting the critical water and sewer system deficiencies in Akhiok. These alternatives are outlined below:

Alternative 1 (worst case scenario)

• Do nothing.

Alternative 2 (best case scenario)

This scenario addresses both major and critical water and sewer system deficiencies. IMPROVEMENT EST.

COST WATER Construct a new modern WTP that satisfies all current regulatory treatment requirements ($3M)

$3M

Construct a new WST and associated piping that will provide adequate chlorine contact time for water disinfection.

$350K

Increase the capacity of Akhiok’s raw water reservoir $600K SEWER Replace the existing community sewage outfall $520K Replace the three existing community septic tanks $450K Provide a new pumper truck for maintaining the septic tanks $125K Provide a sludge disposal facility for accepting sewage solids $700K

$5.75 M



Alternative 3 (minimum corrective action scenario)

This scenario only addresses current critical water and sewer system deficiencies. IMPROVEMENT EST.

COST Water Provide and configure a sand filtration system with coagulant that can produce treated water meeting current regulations

$250K

Provide and modify shipping containers to house the treatment equipment $100K Provide a baffled, pressurized, chlorine contact vessel $120K Provide and install required yard piping to connect new chlorine contact vessel and treatment equipment

$100K

Sewer Replace the existing community sewage outfall $300K Provide a new trailer-mounted vacuum pump and tank for maintaining the septic tanks

$60K

Perform site investigation and obtain permits for a trench-type sludge disposal location

$25K

$955K

Discussion of Corrective Action Alternatives

Alternative 1

Alternative 1 does not address the existing threats to public health and the environment or bring the system into compliance with existing water and wastewater treatment regulations.

Alternative 2

Alternative 2 eliminates the current threats to public health and the environment and would bring the system into compliance with current water and wastewater regulations. These improvements are also anticipated to serve the community’s sanitation needs for the foreseeable future.

Alternative 3

Alternative 3 is comparable to Alternative 2 in terms of bringing the system into regulatory compliance, addressing public health and environment issues, and providing the necessary infrastructure for proper maintenance of the sewage system. However, these improvements are not considered an optimal long-term solution.

The temporary water treatment plant will not be as energy efficient as a new facility and may not be upgradable to satisfy new regulations that may be introduced in the future. A



single filter would be used to minimize capital costs and space requirements instead of the minimum of two filter used in new facilities to provide redundancy. The temporary water treatment system will likely require refurbishment within 10 years.

The dedicated chlorine contact tank will address the need for proper water disinfection, but does not address the need for additional storage of potable water.

The community septic tanks will likely need to be addressed in the near future. These steel tanks are likely in very poor condition after serving in a marine environment.

The simple trench approach for disposing septic sludge may not be feasible, based on the results of a site investigation, engineering analysis, and permitting requirements.

The trailer-mounted vacuum pumper system will be more labor intensive to use than a truck mounted system. However, it may be advantageous and a better fit for Akhiok because any operable full-size truck would be able to pull it, and there are fewer components to maintain.

Conclusions/Recommendations

Based on the result of this study, Akhiok’s water and sewer system has the following critical deficiencies:

• The existing water treatment system does not meet the requirements of the 1989 SWTR

• The existing water treatment system does not meet the requirements of the 2002 LT1ESWTR

• Akhiok’s existing water treatment plant building is structural compromised and poses a health and safety hazard to the operator and any other occupants.

• Akhiok’s sewage outfall is severed near the beach, exposing residents to wastewater

• Akhiok lacks the minimum equipment and facilities necessary to properly maintain their community septic tanks. The current state of the sewage outfall is directly attributable to this deficiency.

The minimum effort required to address these deficiencies is estimated to cost about $955K.

In addition to the critical deficiencies listed above, Akhiok has the following major deficiencies, which are defined as deficiencies that significantly affect the operability of the system or are likely to become critical deficiencies in the near future:

• Akhiok’s three existing community septic tanks are steel construction, and are likely in poor condition after over 40 years operation adjacent to a saltwater coastline. These septic tanks should be replaced before they fail (collapse).

• Akhiok’ raw water source does not have adequate storage

The effort required to address these deficiencies is estimated to cost about $1.05M.

Akhiok 250037 Status Component Inspection Photo Log April 28, 2010

Photograph 1: Akhiok from shore

Photograph 2: Water Treatment Plant

Main entrance


Photograph 3: Source

Photograph 4: Intake Structure at source

Intake Structure


Photograph 5: Raw water sample tap

Photograph 6: Working sand filter (left)

Sample Tap


Photograph 7: Chlorine tank and injection point

Photograph 8: CFE sample tap (hose)

Injection Point

Chlorine injection point

Sample Tap


Photograph 9: Storage tanks

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